i went and checked dpreview.com canon forums and saw where some were having that problem, but it seemed to fix itself if they did not take it back, one even said she pulled on the lens to help it out and never had a problem again, i don't think i'd do that. was battery full charged? some mentioned that. the main thing they said was something about blurs in the corners at full focus, if you have that take it back, now...check dpreview.com canon forums and steves forums has a good canon thing going on there, good luck?
If you feel that the camera is not operating normally, you can call Canon USA's technical support line at: 1-800-828-4040. They will be able to help you out, and tell you if the noise is normal. Alternatively, you could go exchange it and see if the new one is any better.
No Canon product that I have ever bought has had the box wrapped in plastic, apart from the actual camera coming in a bubble-wrap bag, etc.